1. Field of the Invention
The present invention relates to a method for expansion of the display of a volume image of an object region, of the type wherein a first image data set of a larger object region is made available, a second image data set of a smaller object region is acquired, the smaller object region lying within the larger object region, and the image data sets are displayed in combination.
2. Description of the Prior Art
In surgery, compact imaging systems such as mobile x-ray devices, ultrasound devices or endoscope/laparoscope are often used. These modalities, however, offer only a limited field of view for visualization. For surgeons, it is desirable to be able to see the local environment of the treatment region in a larger field of view.
Various options are known in whereby at a time interval prior to surgery, 3-D images of the body, e.g., by means of computed tomography or magnetic resonance tomography, are acquired in order to be able to visualize the local environment with these 3-D images during the surgery. For using pre-surgery images during the surgery, a current local representation of the treatment region appears on a primary monitor, the representation being acquired e.g. with the mobile imaging modality. On a secondary monitor an image superimposition or fusion takes place. The current local representation, e.g. an endoscopic view, is directly superimposed on the overall view from the pre-surgery image. Both views can be shown suitably transparent and in complementary colors. DE 102 10 646 A1 describes such a superimposition of the image data of a 3D imaging modality with the 2D fluoroscopic image of an examination region.